Riveting machine



RIVETING MACHINE John F. Sherrill, Plymouth, Ind., assignor of three-fourths to Eva R. Lemert, Plymouth, Ind., and one-fourth to Indianapolis Bond and Share Corporation, a corporation of Indiana Application May 4, 1956, Serial No. 582,848

Claims. (Cl. 78-42) This invention relates generally to riveting machines and generally to riveting machines of that type having a rotating and reciprocating peening too'l head.

This application is a continuation-in-part of my copending application Serial No. 220,053, filed April 9, 1951, and now abandoned.

The primary object of the invention is to provide novel means for mounting the peening spindle with respect to the hammer, whereby the stroke of the spindle and the force of the blow imparted therethrough to the peening tool may be accurately governed.

A further object of the invention is to arrange the peening tool spindle within a supporting sleeve so arranged as to provide a unitary structure capable of being readily applied to as well as removed from the air hammer, and which embodies means whereby the unit may be accurately adjusted in the riveting head and securely locked in such adjusted positions.

With the foregoing objects in view, together with others which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts, all as will be described more fully hereinafter, illustrated in the drawing, and particularly pointed out in the claims.

In the drawing:

Fig. 1 is a side view of a riveting machine illustrating the application thereto of a sleeve and riveting spindle constructed in accordance with the invention, and

Fig. 2 is a side elevation on an enlarged scale with parts broken away to illustrate specifically the construction and arrangement of the adjustable sleeve and the spindle associated therewith.

In order to adequately describe the invention and the necessity for the structural arrangement thereof, the complete construction of a riveting machine is illustrated and described.

Referring to the drawing which illustrates the preferred embodiment of the invention, the numeral designates a base plate which mounts an upright column 11. At its upper end the column 11 mounts a head portion 12. The head has a laterally projecting part 13 which supports an anvil 14 which preferably mounts a rivet holder 15..

The head 12 has a second laterally projecting portion 16 in the nature of a tubular socket which receives the lower end of an upright column or rigid tube 17. Set screws 18 are provided to clamp the column in the socket 16. The vertical adjustment of the column 17 may be controlled by means of a set screw 19 bearing against the lower end of the column 17 and screw-threaded in a bore of a rigid part 20 projecting laterally from the upright 11 in spaced relation below the head 12. By this construction the column 17 is held rigidly and securely in upright position by means of a socket 16 and the set screws 18 in said socket, and the height or elevation of the column 17 is micrometrically adjusted or controlled by the set screw 19.

A head 21 is mounted on the column 17 and is preferably provided with a plurality of vertically spaced axially aligned split collars 22, 23 and 24 which are slidable upon the column 17. A collar 25 is fixedly mounted upon the column 17 at the portion normally interposed between the collars 22 and 23 and supports a coil spring 26 which bears upon the lower surface of the upper collar 22. A second coil spring 27 is preferably provided hearing against the lower end of the collar 24 and against a collar portion 28 fixedly clamping a platform 29 to the column 17. The springs 26 and 27 normally urge the head 21 to the elevated position illustrated in Fig. 1.

A bracket 31 is clamped or otherwise fixedly secured to the upper end of the column 17 spaced above the head 21 and mounts a power actuated member, here illustrated as a pneumatic cylinder-piston unit 32, which is preferably positioned substantially upright and which has a depending piston plunger 33 projecting therebelow. At its lower free end the plunger 33 is pivoted at 34 to a cam member 35 which is in turn pivoted at 36 to the collar 25. A roller 37 is journaled upon the collar 23 and engages the bottom or camming surface of the cam member 35.

An air line 40 is connected at one end by a fitting 41 to the cylinder 32, and at its opposite end is connected to a valve 42. The valve 42 is of known type and is adjustable to time the operation of a pneumatic circuit. A primary control valve 43 adapted to be operated by a foot pedal 44 is interposed in the pneumatic circuit or network along with the valve 42, and these valves cooperate in known manner to control the time during which the cylinder piston unit 32 is operated following each actuation of the control pedal 44. It will be apparent, therefore, that when the pedal 44 is depressed, the cylinder piston unit 32 is energized with instant lowering of its plunger 33 to move or swing the cam 35 and thereby press against the roller 37 to depress the head 21 against the action of the springs 26 and 27. When the predetermined time interval for which the valve 42 is set has ended, the pneumatic pressure in the cylinder piston unit 32 is automatically relieved and the springs 26 and 27 thereupon become operative to again raise or elevate the head 21.

The front portion of the head 21 is preferably of substantially U-shape and includes a forwardly projecting upper arm 46 and forwardly projecting lower arm 47. The upper arm 46 is provided at its forward end with a split collar 48 in which is tightly clamped the housing 49 of a pneumatic hammer of known type. This hammer housing is preferably provided with an annular ring 50 at its lower end bearing against the lower end of the collar 48. The hammer includes a valve portion 51 including a valve stem 52 which is operated by the finger portion 53 of a lever 54 pivoted at 55. A hose or line 56 leads to a source of air under pressure utilized for the purpose of operating the hammer. The lever 54 is adapted to be operated or tripped by a finger 57 projecting from a valve operator rod 58 carried by an arm 59 clamped or otherwise fixedly secured at 60 to the column 17 above the head. In other words, when the head 21 is urged to lowered position, the lever 54 is caused to strike the projection 57 as the peening tool approaches the rivet holder 15, thereupon actuating the valve 51 and causing the hammer to operate.

The casing 49 of the air hammer has an internally screw-threaded tubular projection or nose 62 at its lower end into which projects the striker portion or hammer head 63 of the pneumatic hammer. The upper end portion of a sleeve 64 is screw-threaded in the nose 62 in axial alignment with the striker 63. A jam nut or lock nut 65 is threaded on the sleeve 64 to lock said sleeve in selected position. The sleeve 64 is provided intermediate its ends with a circumferential flange or collar 66 having suitably disposed bores therein for the reception.

of a spanner wrench or other tool for screwing the sleeve into and out of the nose 62. The sleeve 64 has an axial bore which receives a spindle 67 for slidable rotative movement within the sleeve. The bore of the sleeve 64 is enlarged at 68 and is provided with a beveled seat portion 69. The spindle 67 has an outwardly extending circumferential flange or valve head 70 disposed in the enlarged bore portion 68 and adapted to seat against the beveled valve seat portion 69.

A cap 72 is screw-threaded upon the lower end of the sleeve 64, the inner circumferential wall of said cap cooperating with the enlarged portion 68 of the sleeve 64 to define a chamber receiving the valve head 70 and accommodating vertical or axial movement thereof. The bottom wall 73 ofthe cap 72 is apertured to receive the spindle 67 and preferably mounts a bearing 74 receiving said spindle. A packing 75 encircles the spindle 67 and is held in place by packing nut or backing member 76. The packing 75 provides a seal for the lower end of the chamber within the cap 72, although it will be understood that any other type of sealing means found suitable may be employed for this purpose.

A seal is also desirable between the cap 72 and the lower end of the sleeve 64, and I have shown such seal as a gasket 77 bearing against the upper end of the cap 72 and pressed upon by a lock nut or jam nut 78. The cap 72 mounts a fitting 79 to which an air line 80 is connected, said air line extending from a source of air under pressure. The air line 80 and fitting 79 serve to supply air under pressure to the chamber within the cap 72, which air under pressure acts against the shoulder or valve head 70 to cause it normally to seat against the valve seat 69 and thus seal or close the chamber and at the same time urge the spindle 67 upwardly for engagement with the striker 63 of the air hammer 49.

The lower arm 47 of the head 21 is split or bifurcated and includes an upper bearing sleeve portion 82 Within which the spindle 67 is journaled. A pulley member 83 is positioned below the bearing sleeve 82 and above the lower bearing head 84 carried by the arm 47. The pulley preferably has a hub portion which is splined at 85 to the spindle 67 to accommodate relative endwise movement between the pulley S3 and the spindle. A bearing member 86 carried by the lower sleeve 84 will preferably journal the hub of the pulley 83. At its lower end, preferably projecting beyond the head 84, the spindle 67 mounts a peening tool 87 of any desired or known type, which is adapted to engage the head portion 88 of a rivet supported by the holder and passing through the work pieces 89 and 90 which are to be riveted together.

The platform 29 preferably mounts an electric motor 92 provided with a pulley 93 around which is trained a belt 94 also trained around the pulley 83. A pair of idler pulleys 95 are mounted upon the support 96 adjustably carried by the platform 29.

In the operation of the device, assuming that the lines 56 and 80 are connected to a source of air under pressure in addition to the connection of the valves 42 and 43 to a source of air under pressure, and assuming further that the motor 92 is connected and energized, the device is ready for operation. The rivet 88 and the work pieces 89 and 90 are placed upon the anvil 14 and rivet holder 15, and the pedal 44 is depressed. The motor 92 preferably operates continuously during use of the device and thus drives the belt 94 to cause the spindle 67 to be rotated continuously. The depression of the pedal 44 energizes the cylinder-piston unit 32 to urge the plunger 33 downwardly, thereby operating the cam 35 to lower the unit 21. As the head unit moves downwardly, the valve lever 54 engages the finger 57 at the time that the peening tool 87 engages the rivet head 88 and the pneumatic hammer 49 is caused to operate. Operation of the hammer causes reciprocation of its striker 63,

thereby applying hammer blows to the end of the spindle 67 which are in turn applied through the peening tool 87 to the head of the rivet 88. The supply of air within the chamber defined by the cap 72 acts against the valve head 70 upon the plunger to normally hold that valve against the valve seat 69. Thus, until such time as the lever 54 of the valve 51 is energized, the air within the cap 72 will hold the spindle in upward valve-seating position. The hammer blows imparted by the striker 63 act against the compressed air within the cap 72, restraining the stroke of the spindle and subjecting the spindle to a reverse movement as soon as the impact of the blow of the striker is spent. Thus the stroke of the striker is limited and no reliance upon mechanical return means, such as springs, is required. The valve head 70 seating at 69 provides a normal seal for the upper end of the air chamher. When the striker 63 strikes the plunger to unseat the valve head 70 from its seat 69, this seal is broken. By reason of the fact that the spindle 67 has a rotative reciprocal fit in the sleeve 64, it will be apparent that there is a vent for air which'escapes past the head through the clearance space between the spindle 67 and the sleeve 64. This clearance communicates with a vent port 98 formed in the nose 62 of the hammer so that pressure cannot be trapped behind the valve 70. By reason of this venting action there will be a difference in pressure acting against the opposite faces of the valve head 70 which will cause that valve head to seat at 69 to seal the chamber at all times when the hammer is inoperative.

The stroke of the spindle and the force of the blow imparted therethrough to the peening tool 87 may be varied by adjusting the axial position of the sleeve 64 relative to the nose 62 of the hammer. Thus it is possible to adjust the impact within a wide range from a maximum for forces or power effective upon the device to a minimum. It will be apparent that when the sleeve 64 is screwed fully into the nose 62 so as to substantially engage the end of the striker when the latter is at its retracted position while the valve 70 is seated, a maximum stroke or speed of blow upon the peening head will be secured. From this position of maximum adjustment, any withdrawal of the sleeve 64 to unscrew the same or to shift it outwardly relative to the hose will reduce the stroke of the blow until a point is reached at which the striker 63 of the hammer is unable to engage or strike the spindle 67 at all. Any adjustment desired can be made between these two limits.

It will be apparent that the spline between the spindle 67 and the pulley 83 permits the movement of the spindle relative to the pulley so that the operation of the drive belt 94 will continue to rotate the spindle even though the spindle is reciprocated by the hammer.

While the construction of the device herein illustrated is preferred, it will be understood that changes in the construction may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1. In a riveting machine, a hammer comprising a housing having a reciprocating striker therein, a sleeve having one end in axial alignment with said striker, said sleeve capable of movement toward or away from said striker, means for holding said sleeve in adjusted position, the bore of said sleeve being of uniform diameter from said end for the greater part of the length of said sleeve and enlarged near its opposite end to provide an annular valve seat within said sleeve, a cap mounted on and enclosing said opposite sleeve end, said cap having an enlarged internal bore portion substantially corresponding with the enlarged bore of said sleeve to provide an annular chamber therewith, a spindle rotatably mounted within and of equal diameter with said sleeve bore and extending through said cap and having one end disposed adjacent to saidgstriker, an annular flange aflixed on said spindle of a diameter to slidingly fit within said chamber, means to supply fluid pressure to said chamber against said annular flange to force said spindle in the direction of said striker, and a peening tool atfixed to said spindle.

2. In a riveting machine, a hammer comprising a housing having a reciprocating striker therein, a sleeve secured at one end to said housing in axial alignment with said striker and adjustable longitudinally with respect thereto, means for securing said sleeve in its adjusted positions, the opposite end of said sleeve having its bore enlarged to provide a chamber, a cap covering said opposite end of said sleeve, a spindle rotatably mounted in said sleeve and through said cap with one end disposed adjacent to said striker, an annular flange secured to said spindle and disposed in said chamber, means to supply air under pressure in said chamber against said flange to force said spindle in the direction of said striker, and a peening tool aflixed to said spindle.

3. The combination with a housing having a nose and a reciprocating striker therein, a thread in said nose, a sleeve externally threaded at one end to engage the threads in said nose for adjustment axially with respect to the latter, means for holding said sleeve in locked position, the bore of said sleeve being of uniform diameter from said end for the greater part of the length of said sleeve and enlarged near its opposite end to provide an annular valve seat within said sleeve, a cap mounted on and enclosing said opposite sleeve end, said cap having an enlarged internal bore portion substantially corresponding with the enlarged bore of said sleeve to provide an annular chamber therewith, a spindle rotatably mounted within and of equal diameter with said sleeve bore and extending through said cap and having one end disposed adjacent to said striker, an annular flange aflixed on said spindle of a diameter to slidingly fit within said chamber, means to supply fluid pressure to said chamber against said annular flange to force said spindle in the direction of said striker, and a peening tool afilxed to said spindle.

4. The combination with a housing having a nose and a reciprocating striker therein, a thread in said nose, a sleeve externally threaded at one end to engage the 6 7 threads in said nose for adjustment with respect to the latter, a collar threaded upon said sleeve to abut said nose for holding the sleeve in adjusted positions with respect thereto, the bore of said sleeve being of uniform diameter from said end 'for the greater part of the length of said sleeve and enlarged near its opposite end to provide an annular valve seat within said sleeve, a cap mounted on and enclosing said opposite sleeve end, said cap having an enlarged internal bore portion substantially corresponding with the enlarged bore of said sleeve to provide an annular chamber therewith, a spindle rotatably mounted within and of equal diameter with said sleeve bore and extending through said cap and having one end disposed adjacent to said striker, an annular flange aifixed on said spindle of a diameter to slidingly fit Within said chamber, means to supply fluid pressure to said chamber against said annular flange to force said spindle in the direction of said striker, and a peening tool :aflixed to said spindle.

5. The combination with a housing having a nose and a reciprocating striker therein, a sleeve secured at one end to said nose and adjustable axially with respect thereto, the bore of said sleeve being of uniform diameter from said end for the greater part of the length of said sleeve and enlarged near its opposite end to provide an annular valve seat within said sleeve, a cap threadedly mounted on and enclosing said opposite sleeve end, a collar threaded on said sleeve end and engageable with said cap .to lock the latter in adjusted position upon said sleeve, said cap having an enlarged internal bore portion substantially corresponding with the enlarged bore of said sleeve to provide an annular chamber therewith, a spindle rotatably mounted within and of equal diameter with said sleeve bore and extending through said cap and having one end disposed adjacent to said striker, an annular flange afiixed on said spindle of a diameter to slidingly fit within said chamber, means to supply fluid pressure to said chamber against said annular flange to force said spindle in the direction of said striker, and a peening tool aflixed to said spindle.

No references cited. 

